A clinical psychologist conducted a correlational study to investigate the relationship between daily screen time (in hours) and self-reported sleep quality (on a rating scale of 1 to 10). A sample of 18 participants was used. The psychologist did not predict the direction of the relationship (making it a two-tailed test).
The calculated value of Spearman's rank correlation coefficient (rsr_srs) was 0.465.
| Level of significance for a one-tailed test | 0.05 | 0.025 |
|---|---|---|
| Level of significance for a two-tailed test | 0.10 | 0.05 |
| N=16N = 16N=16 | .429 | .503 |
| 17 | .414 | .485 |
| 18 | .401 | .472 |
| 19 | .391 | .460 |
| 20 | .380 | .447 |
Note: The calculated value of rs r_s\,rs must be equal to or greater than the critical value for statistical significance to be shown.
Is the psychologist's calculated value significant at the p≤0.05 p \le 0.05\,p≤0.05 level? With reference to Table 1, explain your answer.
121 exam-style questions on AQA A Level Psychology Inferential testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.